Browsing Earth and Space Sciences by Title
Now showing items 108-120 of 120
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U/Pb ages of Eocene and younger rocks of the eastern flank of the central Cascade Range, Washington, USA.
(2013-04-17)Geological units located on the eastern flanks of the central Cascade Range, the Summit Conglomerate of Natapoc Mountain, Sugarloaf Peak, Basalt Peak, Horse Lake Mountain, Pole Ridge, Wenatchee Dome at the Cannon mine, and ... -
Uncertainty and Resolution in Full-Waveform, Continuous, Geoacoustic Inversion
(2013-11-14)The ocean geoacoustic inverse problem is the estimation of physical properties of the ocean bottom from a set of acoustic receptions in the water column. The problem is considered in the context of equipment and spatial ... -
Understanding Antarctic ice-stream flow using ice-flow models and geophysical observations
Ice streams are the primary pathway by which Antarctic ice is evacuated to the ocean. Because the Antarctic ice sheets lose mass primarily through oceanic melt and calving, ice-stream dynamics exert a primary control on ... -
Understanding ice-sheet dynamics using geophysical observations and numerical ice-flow models
Mass loss from the world’s ice sheets is one of the largest sources of uncertainty in sea-level rise projections for the 21st century. One way to improve sea-level rise projections is to better understand the processes ... -
Underwater Acoustic Propagation in the Philippine Sea: Intensity Fluctuations
(2013-11-14)In the spring of 2009, broadband transmissions from a ship-suspended source with a 284 Hz center frequency were received on a moored and navigated vertical array of hydrophones over a range of 107 km in the Philippine Sea. ... -
Unlocking the secrets of slow slip in Cascadia using low-frequency earthquakes
Recent discoveries in subduction zones worldwide--including here in Cascadia--have illuminated the once shrouded process of plate convergence below the seismogenic zone. Early geodetic [Dragert, et al., 2001] and seismic ... -
Using local, global, and simulated earthquakes to inform earthquake resilience efforts in the Pacific Northwest
In this dissertation, we investigate how the geometry and rock composition of the Seattle and Tacoma basins influences strong ground motions during local earthquakes by surveying and interpreting strong-motion seismic ... -
Using Low-Frequency Earthquakes to Investigate Slow Slip Processes and Plate Interface Structure Beneath the Olympic Peninsula, WA
This dissertation seeks to further understand the LFE source process, the role LFEs play in generating slow slip, and the utility of using LFEs to examine plate interface structure. The work involves the creation and ... -
Using Salt Accumulations and Luminescence Dating to Study the Glacial History of Taylor Valley, Antarctica
(2012-09-13)Taylor Valley, Antarctica, preserves a record of late Cenozoic Antarctic glaciations. The incursion of the Sea Ice Sheet (RSIS) into lower Taylor Valley during the Last Glacial Maximum is believed to have dammed large ... -
Utilizing Changes in Repeating Earthquakes to Monitor Evolving Processes and Structure Before and During Volcanic Eruptions
Repeating earthquakes are two or more earthquakes that share the same source location and source mechanism, which results in the earthquakes having highly similar waveforms when recorded at a seismic instrument. Repeating ... -
Vegetation and Environmental Changes Across the Cretaceous-Paleogene (K-Pg) Boundary in Northeastern Montana
The Cretaceous-Paleogene (K/Pg) mass extinction was a pivotal event in Earth history; not only did this include the global extinction of non-avian dinosaurs but also the local disappearance of as much as 75% of vertebrate ... -
Wave-Propagation Modeling and Inversion Using Frequency-Domain Integral Equation Methods
Full waveform inverse methods describe the full physics of wave propagation and can potentially overcome the limitations of ray theoretic methods. This work explores the use of integral equation based methods for simulation ... -
What sets the pace of glacier change in a warming world? Examining the roles of climate, geometry, and dynamics
Glaciers are fundamentally sensitive to climate. Following a perturbation in either precipitation or temperature, their extent on the landscape must change in order to re-balance accumulation and melt. This equilibrium ...